Chusetts



LLG. PALMER. ELECTRIC SEAM WELDING APPARATUS. APPLICATION man ocr. 24.1191's.

1,304,703 Patented MyQ, 1919.

l/V VEN TOR L Zap/mer `commonly constructed and arranged, unsat- UNITEDsTATEs PATENT oEEIoE.

LINDLEY GUY PALMER, 0F CINCINNATI, OHIO, ASSIGNOR TO THOMSON ELECTRICWELDING COMPANY, OF LYNN, MASSACHUSETTS, A CORPORATION OF MASSA-CHUSETTS.

ELECTRIC SESAM-WELDING APPARATUS.

Application filed October 24, 1918. Serial No. 259,497.

To au w/wm it may concern:

Be it known that I, LINDLEY GUY PALMER, a citizen of the United States,and a resident of Cincinnati, in the county of Hamilton and State ofOhio, have invented certain new and useful Improvements, in ElectricSeam- Welding Apparatus, of which the following is a specification.

My invention relates to apparatus for elec# tric seam welding in whichheating electric current of large volume but low potential is passedthrough the seam to be Welded to bring the same up to the temperaturerequisite forthe welding operation.

In electric seam welding apparatus as now isfactory results are obtainedespecially in welding seams of any appreciable length' owing to thepotential across the secondary terminals varying as thel roller contacttravels thereby lengthening the secondary circuit.

. Also the heating effect of the current varies at different points inthe seam as more or less of the stock enters the gap of the machine,thereby 'creating a gieater or lessreactance.

The object of my invention Ais to overcome these objectionable featuresin seam welding by maintaining a practically constant difference ofpotential across the-electrodes at all points of travel of the contactroller which makes the seam weld and to reduce the electric loss to aminimum.

To these ends the invention consists in the arrangement of electric seamWelding apparatus hereinafter more particularly described and thenspecified inthe claims.

In thev accompanying drawings, Figure 1 is a diagrammatic illustrationof a form of apparatus arranged in accordancewith this invention.

Fig. 2 is an end elevation of the same.

Fig. 3 illustrates a modification.

Referring to the drawings, the copper casting or heavy mass of copperforming the secondary of the welding transformer is indicated at 1. Saidcopper mass or casting may be of any form desired and may have aprimary2 and a laminated iron core 3 disposed with relation 'to the secondaryand to one another in any of the ways ordinarily practised inthe art.

4, 5 indicate a pair of heavy copper bars .other good conductingmaterial.

forming terminal bars of the secondary and united with the casting 1integrally or otherwise. The said terminal bars 4, 5 extend in oppositedirections from the'casting l butl parallel to one another leaving a gapbetween them for insertion of the work.

v Thework which may be in the form of a lapped seam employed to unitetwo plates of metal on the lapped edges of a tube or cylinder isindicated at 6 and ris preferably supported rin any desired manner onthe lower terminal bar 5.

7 indicates a contact roller of co per or T e said contact rollerbridges the gap between the terminal bars 4, 5 and is progressively fedalong the length of the seam to be welded in any suitable manner as willbe readily understood by those skilled inthe art.

The roller 7 preferably runs in a guiding. groove 8 lformed in the bar4, electrical con' tact being maintained in any suitable manner -as bykeeping surface contacttherewith or by a conducting brush 9 as indicated,in

-F ig. 3. In making the weld, the contact roller travels alongthe seam 6and at each progressive point o-f contact the circuit across the gapbeing completed by the roller 7, the current heats the work and the sameis weldled in the usual and well known manner. As yshown in Fig. 3, thebrush 9 wipes along the underside of the bar 4 and positively conductsthe current to the roller 7. A coiled Aspring around the pivot of thebrush which forl convenience may be the shaft of the roller 7, may beemployed to keep a good contact with the bar 4 as well as assist inapplying pressure to the seam by means of the roller.

By arranging the terminal bars 4, 5 as shown and so that they extend inopposite directions as indicated, the difference of pol tential acrossthe 4gap between the bars at any one point of travel of the roller 7will be the same as at all other points, since any drop of lpotential atthe point of contact of `the roller with the bar 4 due to its greaterdistance from the point or portion of the secondary from which the bar 4extends will be compensated for by the lesserdrop of potential at itsopposite point of contact with the work on the bar 5, which point aswill be seen is correspondingly nearer to the portion or part of thesecondary circuit .from

' a great iengthof work being located in the magnetic gap ie practicailyeiiininated.

It will understood that 'tnerdrawinge mereiy illustrate the principle ofthe'invenbien and that the saine may he embodied in any desired.censtruction or arrangement 'ci' electric seam weiding apparatus, thedetails or which are new Weil known and understood in the art. l i

What claim as myin'vention is:-

En an eieetric seam IWelding apparatus, a pair of transformer Secondaryterminai hars extended parailei to one another but in oppositedirections. and Work-engaging Contact relier adapted 'to travelprogressively in the space between said bars and ccmpiete the electriccircuit therebetween.

v2. In an electric seam Welding appara'tjuej a `pair er" 'transformersecondary terminati bars extended paraei to one another 'but in oppositedirections, one cf said bars forming a Work support and a contact rolleradapted tc progressively engage the seam to be Welded and maintainelectric connection with the ether bar. v

3. vin an eiectric seam Weiding apparatus, a pair ci? transformerSecondary terminal bars extended paraiiei to one another but in oppositedirections7 one of said bare ferming a Work support, a roller Contactadapted to progressively travel in the space 'between said bars andmeans for maintaining electric connection eetween said roiier and saidbars as the relier travels as and for the purpose described.

'Signed at Cincinnati in vthe county ci@ Hamilton and State of @hic thiseighteenth day of October 1918.

LNB'LQY Y PALMER. Witnesses WALTER A. ATSCHEIDER. W. 5. VERBECK.

